Electrocardiographic monitoring and recording apparatus for use in hospital environments has long been known. However, such apparatus is generally bulky and requires that the person being monitored be confined to a bed or chair or an area of very limited mobility.
More recently, compact apparatus has been developed that may be worn or carried by a user for monitoring electrocardiographic data and transmitting that data directly to a telephone handset to recording and analyzing equipment at a centralized location. Such apparatus is exemplified by the Cardiotel ECG transmitter manufactured by Instromedix. Even more recently there has been developed such compact apparatus that both records an electrocardiogram upon command of a user and then, at a convenient subsequent time, plays back and transmits that data through a telephone handset to apparatus at a remote location for analysis of the data. This recording and transmitting apparatus is exemplified by the CardioDiary apparatus manufactured by Instromedix, the TAM II apparatus from Cardiac Data Corp., Cardiobeeper from Survival Tech and the SAMM apparatus from Dart Medical.
While all of these prior devices provide certain benefits, they have suffered from several shortcomings and deficiencies. With their limited recording capabilities, they all depend upon user manipulation at the onset of a symptomatic episode to actuate the apparatus and initiate their recording. This precludes the recording and analysis of electrocardiographic data leading up to the synptomatic episode, which could provide important data surrounding the onset of the episode. Thus, the attending physician may be unable to obtain important data.